“Camouflaging” is generally understood to mean a method of disguising something in such a way that it becomes virtually indistinguishable from its surroundings. For example, camouflaging in the context of war invokes a soldier wearing clothing that makes it difficult to distinguish him or her from the landscape, especially in the midst of heavy bush. In the area of computer information systems, camouflaging can be viewed as a method for protecting sensitive data or information from unauthorized access.
Ideally, a human being can protect an informationally sensitive object if he or she can remember it. Unfortunately, human recall is not always feasible for at least two reasons: 1) there may be too many objects for the person to remember; and 2) even a single object may be too large to remember.
For example, current cryptographic data security techniques secure sensitive information by encrypting it with a key. The original information can only be recovered by decrypting it using the same key or a related key; the security of the data is thus transferred to the security of the key(s). In asymmetric cryptographic methods such as RSA, for example, each user holds a matched pair of keys: a private key and a public key. The private key and the public key form a unique and matched pair such that messages encrypted with the private key (e.g., data, code, or any other digitally represented information, including other cryptographic keys or cryptographic representations of information) can only be decrypted with the corresponding public key, and vice versa. The security of such asymmetric protocols requires keeping the private key confidential to the holder thereof.
For example, Kausik discloses , inter alia, various techniques for cryptographically camouflaging such private keys, and other forms of access-controlled data in U.S. Pat. No. 6,170,058, its associated divisional application (currently pending as Ser. No. 09/750,511), filed Dec. 27, 2000, and an associated continuation-in-part U.S. Pat. No. 6,263,446. These three documents (collectively, “Kausik”) are all incorporated herein by reference in their entirety. Another type of camouflaging, known as “generation camouflaging” also provides a system that is relatively secure from the kinds of hacker attacks on encrypted data systems which are described by Kausik. Generation camouflaging is discussed and claimed in a co-pending application, Ser. No. 09/874,795, filed by Hird on Jun. 5, 2001 (hereafter, “Hird”), and incorporated herein by reference in its entirety. Unlike Kausik's cryptographic camouflaging, however, Hird's generation camouflaging aims at regenerating private keys without storing the private key bit strings, either encrypted or unencrypted. Thus, generation camouflaging goes beyond Kausik, in that it does not require the secured objects to be stored in any manner (either encrypted or unencrypted), either within the wallet or in any other component of the system.
The present application extends the techniques of Hird to still other techniques for camouflaging computer-representable state information, as will be described in the sections following.